Huge cuts mean room for manoeuvre is tight

Boris Johnson's grand announcement today of investment in London's transport system highlights what will be perhaps the biggest battleground in his bid for re-election next year.

Transport has consistently shown up as Londoners' biggest concern in poll after poll. Boris has found himself hobbled by a long time frame for Tube upgrades and by the collapse of the Public Private Partnership that was supposed to deliver them - as well as by delays in the upgrade of the Jubilee line. Hence his effort to talk up what he hopes to accomplish over the next four years.

Much here is welcome: Crossrail; upgrades for three Underground lines and new trains on four more; new rules on roadworks; changes to traffic lights.

Johnson can take some credit for this package, and across the board, it does amount to a big investment. But most of these plans were announced years ago: this is essentially a repackaging exercise. The real news here is the extra £2.6 billion in cuts over the next seven years, in addition to £5 million already announced.

Transport for London is adamant that the cuts simply remove waste. But £460 million will be cut from subsidies to bus operators: we will see whether they are willing to take that hit to their profits.

Johnson's room for manoeuvre is tight and getting tighter. Yet if he can deliver improvements, it would be an achievement that would be hard for his opponent to match.